A light case (7)
I believe the answer is:
lantern
'a light case' is the definition.
(I've seen this in another clue)
'a light' is the wordplay.
I cannot quite see how this works, but
'a' could be 'an' and 'an' is located in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for lantern that I've seen before include "Lamp with protective transparent casing" , "Transparent case for holding a light" , "Enclosed light" , "Portable lamp case" , "It illuminates" .)